`#3107.101107`

`-3^2 + {-54 \div [-2^8 + 7] * (-2)^2}`

`= -9 + [-54 \div (-256 + 7) * 4]`

`= -9 + [-54 \div (-249) * 4]`

`= -9 + (18/83 * 4)`

`= -9 + 72/83`

`= -675/83`

______

`31 * (-18) + 31 * (-81) - 31`

`= 31 * (-18 - 81 - 1)`

`= 31 * (-100)`

`= -3100`

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`(-12) * 47 + (-12) * 52 + (-12)`

`= (-12) * (47 + 52 + 1)`

`= (-12) * 100`

`= -1200`

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`13 * (23 + 22) - 3 * (17 + 28)`

`= 13 * 45 - 3 * 45`

`= 45 * (13 - 3)`

`= 45 * 10`

`= 450`

____

`-48 + 48 * (-78) + 48 * (-21)`

`= 48 * (-1 - 78 - 21)`

`= 48 * (-100)`

`= -4800`

a) \(\frac{11}{24}-\frac{5}{41}+\frac{13}{24}+0,5-\frac{36}{41}\)

= \(\frac{11}{24}-\frac{5}{41}+\frac{13}{24}+\frac{1}{2}-\frac{36}{41}\)

= \(\frac{1}{2}-\left\{\frac{11}{24}+\frac{13}{24}\right\}-\left\{\frac{5}{41}+\frac{36}{41}\right\}\)

=\(\frac{1}{2}-\frac{24}{24}-\frac{41}{41}\)

=\(\frac{1}{2}-1-1\)

=\(\frac{-3}{2}\)

b) \(-12:\left\{\frac{3}{4}-\frac{5}{6}\right\}^2\)

= \(-12:\left\{\frac{9}{12}-\frac{10}{12}\right\}^2\)

= \(-12:\left\{\frac{-1}{12}\right\}^2\)

= \(-12:\frac{1}{144}\)

= \(-12.144\)

= -1728

c) \(\frac{7}{23}.\left[\left(\frac{-8}{6}\right)-\frac{45}{18}\right]\)

= \(\frac{7}{23}.\left[\left(\frac{-24}{18}\right)-\frac{45}{18}\right]\)

= \(\frac{7}{23}.\left(\frac{-23}{6}\right)\)

= \(\frac{-7}{6}\)

d) \(23\frac{1}{4}.\frac{7}{5}-13\frac{1}{4}:\frac{5}{7}\)

= \(23\frac{1}{4}.\frac{7}{5}-13\frac{1}{4}.\frac{7}{5}\)

= \(\left\{23\frac{1}{4}-13\frac{1}{4}\right\}.\frac{7}{5}\)

= \(10.\frac{7}{5}\)

= 14

e) (1+23−14).(0,8−34)2

= (1+23−14).(\(\frac{4}{5}\)−34)2

= \(\left(\frac{12}{12}+\frac{8}{12}-\frac{3}{12}\right).\left(\frac{16}{20}-\frac{15}{20}\right)^2\)

= \(\frac{17}{12}.\left(\frac{1}{20}\right)^2\)

= \(\frac{17}{20}.\frac{1}{400}\)

= \(\frac{17}{8000}\)

a) \(\left(-28\right).\left(-3\right).\left(+4\right).\left(-7\right)=\left(+84\right).\left(+4\right).\left(-7\right)=\left(+336\right).\left(-7\right)=\left(-2352\right)\)

b) \(2.8.\left(-14\right).\left(-3\right)=16.\left(-14\right).\left(-3\right)=\left(-224\right).\left(-3\right)=672\)

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làm cụ thể ra hộ mình

bai de the ma cung hoi

\(\frac{7}{18}.\left(\frac{-12}{23}-\frac{4}{15}\right)+\frac{7}{18}.\left(\frac{8}{30}+\frac{35}{23}\right)\)

\(=\frac{7}{18}.\left(\frac{-12}{23}-\frac{4}{15}\right)+\frac{7}{18}.\left(\frac{4}{15}+\frac{35}{23}\right)\)

\(=\frac{7}{18}.\left(\frac{-12}{23}-\frac{4}{15}+\frac{4}{15}+\frac{35}{23}\right)\)

\(=\frac{7}{18}.[\left(\frac{-12}{23}+\frac{35}{23}\right)+\left(\frac{-4}{15}+\frac{4}{15}\right)]\)

\(=\frac{7}{18}.1+0\)

\(=\frac{7}{18}\)

_Chúc bạn học tốt_

\(=5+\dfrac{1}{5}-\dfrac{2}{9}-2+\dfrac{1}{23}+\dfrac{73}{35}-\dfrac{5}{6}-8-\dfrac{2}{7}+\dfrac{1}{18}\)

\(=-5+\left(\dfrac{1}{5}-\dfrac{2}{7}+\dfrac{73}{35}\right)+\left(\dfrac{-2}{9}-\dfrac{5}{6}+\dfrac{1}{18}\right)+\dfrac{1}{23}\)

\(=-5+\dfrac{7-10+73}{35}+\dfrac{-4-15+1}{18}+\dfrac{1}{23}\)

\(=-5+2-1+\dfrac{1}{23}=-4+\dfrac{1}{23}=-\dfrac{91}{23}\)

a) Ta có: \(\dfrac{5}{8}+\dfrac{3}{17}+\dfrac{4}{18}+\dfrac{20}{-17}+\dfrac{-2}{9}+\dfrac{21}{56}\)

\(=\left(\dfrac{3}{17}-\dfrac{20}{17}\right)+\left(\dfrac{2}{9}-\dfrac{2}{9}\right)+\left(\dfrac{5}{8}+\dfrac{3}{8}\right)\)

\(=-1+1=0\)

b) Ta có: \(\left(\dfrac{9}{16}+\dfrac{8}{-27}\right)+\left(1+\dfrac{7}{16}+\dfrac{-19}{27}\right)\)

\(=\left(\dfrac{9}{16}+\dfrac{7}{16}\right)+\left(\dfrac{-8}{27}-\dfrac{19}{27}\right)+1\)

=1-1+1=1